ALAN
KEPKA,
PH.D.
JOSEPH
BIENIARZ,
LINDA
MUTSCHLER,
NIRANJANA
B.S.
SHAH,
ANTONIO Chicago,
M.D.
M.D.
SCOMME~NA,
M.D.
Illanois
A versatile system has been developed for off-line computerized quantitation of uterine contr~tili~. It in~l~es t~~lation and d~~lay of interim, freq~ncy, resting tone, ute?~ne activity, cum~tive area below the pressure curve, and average intr~u~~‘~e pressure. Its advantages and drawbacks are compared with the conventional method arti with an adopted on-line labor su~eil~~e system.
EACH UTERINE contraction reduces placental perfusion and forms a transient stress to the fetus, who may be damaged by excessive contractility or by prolonged duration of labor.’ Precise quantitation of uterine contractility is of basic importance for prospective evaluation of the fetal condition during labor. External monitoring cannot serve this purpose because it provides reliable measurements of the frequency of uterine contractions only. Direct recording of intrauterine pressure through a catheter inserted into the amniotic cavity represents the sum total of uterine dynamics and provides reliable measurements of the following basic factors needed for precise quantitation’: (I) resting tone-the lowest intrauterine pressure between two uterine contractions measured in millimeters of mercury; (2) intensity-the highest elevation of intrauterine pressure caused by a uterine
contraction measured in millimeters of mercury; (3) frequency-expressed as the number of contractions per 10 minutes, calculated from the time interval between the peaks of two neighboring contractions; (4) activity-the product of intensity by frequency of uterine contractions expressed in Montevideo units (MU) i.e., millimeters of mercury of intensity per 10 minutes of labor. The progress of labor is directly related to the intensity and the frequency of contractions so that uterine activity expressing both parameters in one numerical value is a good indicator of uterine dynamics and its effect on the fetus. This simple method has found general acceptance in the literature. Still, it is too time consuming to take the measurements from the analog recording, tabulate and calculate the means for each parameter under study in 10 and 30 minutes intervals throughout labor. Therefore, this quantitation could not be used prospectively for labor surveillance, only retrospectively after labor, for research purposes. In recent years the availability of highly efficient computerized techniques for automated monitoring of biologic phenomena formed an attractive alternative to the conventional methods. Braaksma and associate9 compared the results obtained by conventional and by digital quantitation of’ merine contractility in nonpregnant women and found good agreement between both methods. Flowers and associates” described a digital computer alerting the obstetrician to uterine hypertonus, hyper-
From the Laboratory of Uterine Physiology,
af
D~ar~ent Obstetrics and G9nec~~o~, and the sediment of Medic Physics, betel Reese ~os~i~~ and Medical Center, and the P&her School ofMedi&e of the Oniversitj of Chicago.
This study utas bared ~~~~00, Research
by The Vp~oh~ Coming,
~~~igan, and the ~~~~ Fnstitute Council.
Receiuedforpublication
October&?,
Reese redbud
1974.
Revised November22,1974. Accepted November
25, 1974.
R~~‘nt reqwsts: Dr. Alan Kepku, Marl Medical Center, 29th St. and El& Ave., Illinois 60616.
Reese Chkago,
246
Uterine contractility data processing systefr
247
UTERtWe
120
0
L
!
!
!
!
!
!
!
!
’
!
!
0
!
L 2
!
! 4
s
’ 6
*
’ 6
’
’ 10
’
’ TIME
IHOURSI
Fig. 1. Uterine contractility pattern in midtrimester abortion induced by repeated injections of 61,cg of Is-me-PGE, intramuscularly every hour in a gravida 2, para 0 woman, age 21, 20 weeks preg nant. Means and SD of factors under study were computed off-line and displayed in 10 minute intervals. Note the immediate rise in the resting tone and in the frequency of uterine conrractions. whereas their intensity and activity increased gradually.
contractility, or signs of fetal distress. Similarly Chik and associates* programmed a classification of FHR patterns by their relation to associated intrauterine pressure patterns. Hon and Paul5 quantitated precisely uterine activity in labor by sampling every second the voltage correlated to intrauterine pressure, and in this way derived the cumulative area below the pressure curve for the duration of labor. This method has a definite advantage of greater exactitude than conventional quantitation, which samples only the lowest and the highest points of the pressure curve. On the other hand, the conventional method gives information missing in the former methods: whether the increase in uterine activity is due to changes in the resting tone, in the intensity, or in the frequency of uterine contractions. This information is of great value in recognizing imminent
fetal distress and in the choice of the most appropriate treatment. As a first step toward a full computerized labor surveillance we have developed a digital data zxcquisition system by an off-line PDPSIE computer* programmed for precise quantitation of the area below the pressure curve, resting tone, intensity, frequency of contractions, and uterine activity. Our aim was to have the means and standard deviations of all these values tabulated and visually displayed in 10 minute intervals during the whole duration of labor. The automated digital system was implemented in a study of the oxytocic effect of synthetic pros~~~andins for induction of midtrimester abortion.” In this study uterine contractions were so frequent that their precise *Digital Equipment
Corp., Maynard. Massachusetts.
248
Kepka
et al.
Fig. 2. Precise quantita~on of uterine contractility obtained in the same case as in Fig. 1 by computing the cumulative area below the pressure curve (upper square). The mean intrauterine pressure exerted on the conceptus (lower square) is inversely related to the induction-abortion time.
quantitation by conventional methods was extremely time consuming. The voltage driving the pressure recording pen on a Hewlett-Packard Model 8020 A cardiotocograph* was sampled by a Datacap Series D analog to digital converter? at 3 second intervals. The converter drove a paper tape punch on a standard Series 33 Teletype accomodating I2 hours of patient data on a 1,200 foot roll of paper tape, which could be replenished in less than 1 minute. An automatic take-up reel was used to wind the data tape. The teletype was enclosed in a Gates Model 685G acoustical cover which reduced noise by a factor of 80 per cent. During cardiotocograph calibration a signal button was pressed on the analog to digital converter at known *Hewlett-Packard Co., Palo Alto, California. t Datacap Inc., Chicago, Illinois.
pressure levels of 0, 25, and 50 mm. Hg, producing a minus sign preceding the respective digits on the data tape. In a similar way time was recorded on the data tape by pressing the button exactly on each hour during the recording. The paper tape was read into a TC08 Dual Dectape* computer and recorded on one of the magnetic tapes by a high-speed Remex reader? operating at 300 characters per second. Each hour of patient data required less than 1 minute to read. Computer programs were written in FOCAL in order to first reduce and then to analyze the raw data recorded on magnetic tape. The analysis began by reading the calibration file and determining the relation between output voltage in millivolts and pressure *Digital Equipment Corp. TEx-Cell-0 Corp., Santa Ana, California.
Volume Number
123 3
in mil~meters of mercury. The relation between voltage and pressure is direct and linear to better than 1 per cent. The information abstracted from the raw data consisted of the values of (1) maximum pressure, (2) minimum pressure preceeding the maximum, (3) the times when these events occur, and (4) the area under the pressure versus time curve. The data were further refined by excluding the contractions of less than 5 mm. Hg intensity, thus disregarding small fluctuations around the resting tone. Only slow variations in intrauterine pressure caused by contractions were considered, excluding sharp spikes caused by vomiting, etc. This was accomplishedin the computer program by requiring that uterine pressure increases for at least 12 seconds before testing for maximum pressure. In order to avoid that sharp spikesat the peak of uterine contraction caused by bearing down efforts are read as the intensity of uterine contraction, maximum pressure 10 Fr cent greater than uterine pressuresrecorded 3 secondsearlier were discarded. Otherwise the latter pressure was subsequentfy tested for being the maximum. In the final analysisthe reduced data file wasusedto compute and tabulate the averagesand standard deviations of parameters of interest (intensity of contractions, resting tone, frequency of contractions, uterine activity, etc.) in 10minute time intervals. The final data file was recorded on a magnetic tape about one tenth the size of the original raw data file. It could be accessedby other programs which allow for retabulating the results or obtaining a graphical display (Fig. I) using a Hewlett-Packard Model 7004B X-Y recorder. The routines described above require approximately 2 hours of PDP81E computer time for the complete analysisof 12 hours of patient data. We have obtained precise quantitation of uterine c~~ntractility in 40 inductions of midtrinlester abortion with a fraction of the effort which would be necessary by the useof the c~)nventional method. A preliminary comparison between results obtained in eight records studied by the digital and by the conventional methods has shown differences of less than 3 per cent in quantitation of various parameters under study. These differences were found to be due to errors in measurement or calculations by the conventional method. Artifacts in the digital method were weeded out by developing the computer program asdescribed above. Striking differences in the graphical display of a mean rfr SD from previous and following values in-
Uterine contractility data processing system
249
dicate poor recording (e.g.. hour 1 on Fig. 1). The respective values have been excluded from analysis. The cumulative area below the pressure curve (Fig. 2) showed results similar to those previously reported by Hon and Paul.5This quantitation is more exact than the analysis of uterine contractility depicted in i;ig. 1 becausethe area beiow the pressurecurve wasobtained with greater resolution in time. Still, the vabie of specific selectivity in analyzing the uterine contractility pattern obtained in our processing system is eGdent from the following comparison. The cumulative pressurearea of 8,000 mm. Hg-min. computed during the first 5 hours of a midtrimester prostagiandin abortion (Fig. 2) is similar to that recorded by Hon and Paul5over a comparable period of time in a primigravida in labor from 5 cm. cervical dilatation to delivery. However, the contra&&v pattern depicted in Fig. 1. with hypertonicity 20 to 311mm. Hg, and frequency of 8 to 14 contractions per 10 minutes is unlikely to be seenin normal labor. Such a pattern would suggestabruptio placentae and vould necessitateimmediate treatment to avoid seven- fetal distress. The mean intrauterine pressure depicted in the lower part of Fig. 2 is also derived from the voltage curve, and according to our observationsit. is inversely related to the induction-a~rtion time. Thr; significance of this parameter in term labor will be investigated. Our observations have shown that precise qumtitation of uterine contractility can be greatly accelerated with the use of an off-line computer. The system described can be used efficiently for retrospective studies of uterine contractility, e.g., those of oxytocic effects of prostaglandins in midtrimester abortions. Conventional quanti~tion of uterine contractility in those studiesis usually limited to very few casesbecause of the amount of work involved. However, the above off-line systemisstill inadequate for prospective labor surveillance becauseof the inherent delay in information. An on-line warning device was used in labor for the diagnosisof ominous fetal heart rate patterns.7 Our preliminary report. forms the first step in programming an on-line computer for immediate display of precisequantitation of both uterine contractilrty and fetal heart rate, which we are setting up at the present time. In this way the advantagesof a fully automated surveillance systemfor the prospective managementof labor will be available.
REFERENCES
1. Caldeyro-Barcia, R., and Alvarex, H.: Abnormal uterine action in labour, J. Obstet. Gynaecol. Br. Emp. 59: 696, 1952. 2. Braaksma, J. T., Veth, A. F. L., Janssens, J., Stoke, L., Eskes, T., Hein, P., and van der Weide, H.: A comparison of digital and nondigital analysis of contraction records obtained from the nonpregnant uterus in vivo, AM. J. OBSTET. GYNECOL. 110: 1075, 1971. 3. Flowers, C., Hinkley, C., and Hatcher, J.: The use of a digital computer in monitoring the condition of the fetus during labor, AM. J. OBSTET. GYNECOL. 111: 644, 1971.
4. Chik, L., Rosen, M., Hirsch, V., and Sokol, R.: Programmed identification of fetal heart rate deceleration patterns, AM. J. OBSTET. GYNECOL. 119: 816, 1974. 5. Hon. E., and Paul, R.: Quantitation of uterine activity, Obstet. Gynecol. 42: 368, 1973. 6. Bieniarz, J., Hunter, G., Altamirano, Z., and Scommegna, A.: Efficacy and acceptability of prostaglandin 15(s) and 15-methyl ester for induction of midtrimester abortion. AM. J. OBSTET. GYNECOL. 120: 840, 1974. 7. Yeh, S., Jilek, J., and Hon, E.: On-line diagnosis of ominous fetal heart rate patterns: A warning device, AM. J. OBSTET. GYNECOL. 118: 559, 1974.
Colloquia in Gynecology-Andrology Two C. S. Mott Center Colloquia in reproductive physiology will be held at Wayne State University School of Medicine, Detroit, Michigan. 1. Sexual Maturity: Endocrine and Clinical Parameters, February 19, 1976. 2. Techniques in Human Andrology (testicular biopsy; physical, immunologic, and bacterial evaluation of semen; in vivo and in vitro tests of cervical mucus), May 6, 1976. Deadline for submitting abstracts of research papers and registration is January, 1976. Physiology For further information write to: Dr. E. S. E. Hafez, Reproductive Laboratories, C. S. Mott Center for Human Growth and Development, Wayne State University, 275 E. Hancock, Detroit, Michigan 48201. Telephone: (313) 577-1011.
KEPKA,
PH.D.
JOSEPH
BIENIARZ,
LINDA
MUTSCHLER,
NIRANJANA
B.S.
SHAH,
ANTONIO Chicago,
M.D.
M.D.
SCOMME~NA,
M.D.
Illanois
A versatile system has been developed for off-line computerized quantitation of uterine contr~tili~. It in~l~es t~~lation and d~~lay of interim, freq~ncy, resting tone, ute?~ne activity, cum~tive area below the pressure curve, and average intr~u~~‘~e pressure. Its advantages and drawbacks are compared with the conventional method arti with an adopted on-line labor su~eil~~e system.
EACH UTERINE contraction reduces placental perfusion and forms a transient stress to the fetus, who may be damaged by excessive contractility or by prolonged duration of labor.’ Precise quantitation of uterine contractility is of basic importance for prospective evaluation of the fetal condition during labor. External monitoring cannot serve this purpose because it provides reliable measurements of the frequency of uterine contractions only. Direct recording of intrauterine pressure through a catheter inserted into the amniotic cavity represents the sum total of uterine dynamics and provides reliable measurements of the following basic factors needed for precise quantitation’: (I) resting tone-the lowest intrauterine pressure between two uterine contractions measured in millimeters of mercury; (2) intensity-the highest elevation of intrauterine pressure caused by a uterine
contraction measured in millimeters of mercury; (3) frequency-expressed as the number of contractions per 10 minutes, calculated from the time interval between the peaks of two neighboring contractions; (4) activity-the product of intensity by frequency of uterine contractions expressed in Montevideo units (MU) i.e., millimeters of mercury of intensity per 10 minutes of labor. The progress of labor is directly related to the intensity and the frequency of contractions so that uterine activity expressing both parameters in one numerical value is a good indicator of uterine dynamics and its effect on the fetus. This simple method has found general acceptance in the literature. Still, it is too time consuming to take the measurements from the analog recording, tabulate and calculate the means for each parameter under study in 10 and 30 minutes intervals throughout labor. Therefore, this quantitation could not be used prospectively for labor surveillance, only retrospectively after labor, for research purposes. In recent years the availability of highly efficient computerized techniques for automated monitoring of biologic phenomena formed an attractive alternative to the conventional methods. Braaksma and associate9 compared the results obtained by conventional and by digital quantitation of’ merine contractility in nonpregnant women and found good agreement between both methods. Flowers and associates” described a digital computer alerting the obstetrician to uterine hypertonus, hyper-
From the Laboratory of Uterine Physiology,
af
D~ar~ent Obstetrics and G9nec~~o~, and the sediment of Medic Physics, betel Reese ~os~i~~ and Medical Center, and the P&her School ofMedi&e of the Oniversitj of Chicago.
This study utas bared ~~~~00, Research
by The Vp~oh~ Coming,
~~~igan, and the ~~~~ Fnstitute Council.
Receiuedforpublication
October&?,
Reese redbud
1974.
Revised November22,1974. Accepted November
25, 1974.
R~~‘nt reqwsts: Dr. Alan Kepku, Marl Medical Center, 29th St. and El& Ave., Illinois 60616.
Reese Chkago,
246
Uterine contractility data processing systefr
247
UTERtWe
120
0
L
!
!
!
!
!
!
!
!
’
!
!
0
!
L 2
!
! 4
s
’ 6
*
’ 6
’
’ 10
’
’ TIME
IHOURSI
Fig. 1. Uterine contractility pattern in midtrimester abortion induced by repeated injections of 61,cg of Is-me-PGE, intramuscularly every hour in a gravida 2, para 0 woman, age 21, 20 weeks preg nant. Means and SD of factors under study were computed off-line and displayed in 10 minute intervals. Note the immediate rise in the resting tone and in the frequency of uterine conrractions. whereas their intensity and activity increased gradually.
contractility, or signs of fetal distress. Similarly Chik and associates* programmed a classification of FHR patterns by their relation to associated intrauterine pressure patterns. Hon and Paul5 quantitated precisely uterine activity in labor by sampling every second the voltage correlated to intrauterine pressure, and in this way derived the cumulative area below the pressure curve for the duration of labor. This method has a definite advantage of greater exactitude than conventional quantitation, which samples only the lowest and the highest points of the pressure curve. On the other hand, the conventional method gives information missing in the former methods: whether the increase in uterine activity is due to changes in the resting tone, in the intensity, or in the frequency of uterine contractions. This information is of great value in recognizing imminent
fetal distress and in the choice of the most appropriate treatment. As a first step toward a full computerized labor surveillance we have developed a digital data zxcquisition system by an off-line PDPSIE computer* programmed for precise quantitation of the area below the pressure curve, resting tone, intensity, frequency of contractions, and uterine activity. Our aim was to have the means and standard deviations of all these values tabulated and visually displayed in 10 minute intervals during the whole duration of labor. The automated digital system was implemented in a study of the oxytocic effect of synthetic pros~~~andins for induction of midtrimester abortion.” In this study uterine contractions were so frequent that their precise *Digital Equipment
Corp., Maynard. Massachusetts.
248
Kepka
et al.
Fig. 2. Precise quantita~on of uterine contractility obtained in the same case as in Fig. 1 by computing the cumulative area below the pressure curve (upper square). The mean intrauterine pressure exerted on the conceptus (lower square) is inversely related to the induction-abortion time.
quantitation by conventional methods was extremely time consuming. The voltage driving the pressure recording pen on a Hewlett-Packard Model 8020 A cardiotocograph* was sampled by a Datacap Series D analog to digital converter? at 3 second intervals. The converter drove a paper tape punch on a standard Series 33 Teletype accomodating I2 hours of patient data on a 1,200 foot roll of paper tape, which could be replenished in less than 1 minute. An automatic take-up reel was used to wind the data tape. The teletype was enclosed in a Gates Model 685G acoustical cover which reduced noise by a factor of 80 per cent. During cardiotocograph calibration a signal button was pressed on the analog to digital converter at known *Hewlett-Packard Co., Palo Alto, California. t Datacap Inc., Chicago, Illinois.
pressure levels of 0, 25, and 50 mm. Hg, producing a minus sign preceding the respective digits on the data tape. In a similar way time was recorded on the data tape by pressing the button exactly on each hour during the recording. The paper tape was read into a TC08 Dual Dectape* computer and recorded on one of the magnetic tapes by a high-speed Remex reader? operating at 300 characters per second. Each hour of patient data required less than 1 minute to read. Computer programs were written in FOCAL in order to first reduce and then to analyze the raw data recorded on magnetic tape. The analysis began by reading the calibration file and determining the relation between output voltage in millivolts and pressure *Digital Equipment Corp. TEx-Cell-0 Corp., Santa Ana, California.
Volume Number
123 3
in mil~meters of mercury. The relation between voltage and pressure is direct and linear to better than 1 per cent. The information abstracted from the raw data consisted of the values of (1) maximum pressure, (2) minimum pressure preceeding the maximum, (3) the times when these events occur, and (4) the area under the pressure versus time curve. The data were further refined by excluding the contractions of less than 5 mm. Hg intensity, thus disregarding small fluctuations around the resting tone. Only slow variations in intrauterine pressure caused by contractions were considered, excluding sharp spikes caused by vomiting, etc. This was accomplishedin the computer program by requiring that uterine pressure increases for at least 12 seconds before testing for maximum pressure. In order to avoid that sharp spikesat the peak of uterine contraction caused by bearing down efforts are read as the intensity of uterine contraction, maximum pressure 10 Fr cent greater than uterine pressuresrecorded 3 secondsearlier were discarded. Otherwise the latter pressure was subsequentfy tested for being the maximum. In the final analysisthe reduced data file wasusedto compute and tabulate the averagesand standard deviations of parameters of interest (intensity of contractions, resting tone, frequency of contractions, uterine activity, etc.) in 10minute time intervals. The final data file was recorded on a magnetic tape about one tenth the size of the original raw data file. It could be accessedby other programs which allow for retabulating the results or obtaining a graphical display (Fig. I) using a Hewlett-Packard Model 7004B X-Y recorder. The routines described above require approximately 2 hours of PDP81E computer time for the complete analysisof 12 hours of patient data. We have obtained precise quantitation of uterine c~~ntractility in 40 inductions of midtrinlester abortion with a fraction of the effort which would be necessary by the useof the c~)nventional method. A preliminary comparison between results obtained in eight records studied by the digital and by the conventional methods has shown differences of less than 3 per cent in quantitation of various parameters under study. These differences were found to be due to errors in measurement or calculations by the conventional method. Artifacts in the digital method were weeded out by developing the computer program asdescribed above. Striking differences in the graphical display of a mean rfr SD from previous and following values in-
Uterine contractility data processing system
249
dicate poor recording (e.g.. hour 1 on Fig. 1). The respective values have been excluded from analysis. The cumulative area below the pressure curve (Fig. 2) showed results similar to those previously reported by Hon and Paul.5This quantitation is more exact than the analysis of uterine contractility depicted in i;ig. 1 becausethe area beiow the pressurecurve wasobtained with greater resolution in time. Still, the vabie of specific selectivity in analyzing the uterine contractility pattern obtained in our processing system is eGdent from the following comparison. The cumulative pressurearea of 8,000 mm. Hg-min. computed during the first 5 hours of a midtrimester prostagiandin abortion (Fig. 2) is similar to that recorded by Hon and Paul5over a comparable period of time in a primigravida in labor from 5 cm. cervical dilatation to delivery. However, the contra&&v pattern depicted in Fig. 1. with hypertonicity 20 to 311mm. Hg, and frequency of 8 to 14 contractions per 10 minutes is unlikely to be seenin normal labor. Such a pattern would suggestabruptio placentae and vould necessitateimmediate treatment to avoid seven- fetal distress. The mean intrauterine pressure depicted in the lower part of Fig. 2 is also derived from the voltage curve, and according to our observationsit. is inversely related to the induction-a~rtion time. Thr; significance of this parameter in term labor will be investigated. Our observations have shown that precise qumtitation of uterine contractility can be greatly accelerated with the use of an off-line computer. The system described can be used efficiently for retrospective studies of uterine contractility, e.g., those of oxytocic effects of prostaglandins in midtrimester abortions. Conventional quanti~tion of uterine contractility in those studiesis usually limited to very few casesbecause of the amount of work involved. However, the above off-line systemisstill inadequate for prospective labor surveillance becauseof the inherent delay in information. An on-line warning device was used in labor for the diagnosisof ominous fetal heart rate patterns.7 Our preliminary report. forms the first step in programming an on-line computer for immediate display of precisequantitation of both uterine contractilrty and fetal heart rate, which we are setting up at the present time. In this way the advantagesof a fully automated surveillance systemfor the prospective managementof labor will be available.
REFERENCES
1. Caldeyro-Barcia, R., and Alvarex, H.: Abnormal uterine action in labour, J. Obstet. Gynaecol. Br. Emp. 59: 696, 1952. 2. Braaksma, J. T., Veth, A. F. L., Janssens, J., Stoke, L., Eskes, T., Hein, P., and van der Weide, H.: A comparison of digital and nondigital analysis of contraction records obtained from the nonpregnant uterus in vivo, AM. J. OBSTET. GYNECOL. 110: 1075, 1971. 3. Flowers, C., Hinkley, C., and Hatcher, J.: The use of a digital computer in monitoring the condition of the fetus during labor, AM. J. OBSTET. GYNECOL. 111: 644, 1971.
4. Chik, L., Rosen, M., Hirsch, V., and Sokol, R.: Programmed identification of fetal heart rate deceleration patterns, AM. J. OBSTET. GYNECOL. 119: 816, 1974. 5. Hon. E., and Paul, R.: Quantitation of uterine activity, Obstet. Gynecol. 42: 368, 1973. 6. Bieniarz, J., Hunter, G., Altamirano, Z., and Scommegna, A.: Efficacy and acceptability of prostaglandin 15(s) and 15-methyl ester for induction of midtrimester abortion. AM. J. OBSTET. GYNECOL. 120: 840, 1974. 7. Yeh, S., Jilek, J., and Hon, E.: On-line diagnosis of ominous fetal heart rate patterns: A warning device, AM. J. OBSTET. GYNECOL. 118: 559, 1974.
Colloquia in Gynecology-Andrology Two C. S. Mott Center Colloquia in reproductive physiology will be held at Wayne State University School of Medicine, Detroit, Michigan. 1. Sexual Maturity: Endocrine and Clinical Parameters, February 19, 1976. 2. Techniques in Human Andrology (testicular biopsy; physical, immunologic, and bacterial evaluation of semen; in vivo and in vitro tests of cervical mucus), May 6, 1976. Deadline for submitting abstracts of research papers and registration is January, 1976. Physiology For further information write to: Dr. E. S. E. Hafez, Reproductive Laboratories, C. S. Mott Center for Human Growth and Development, Wayne State University, 275 E. Hancock, Detroit, Michigan 48201. Telephone: (313) 577-1011.
