Roberto Rivera

Preliminary observations on the return of ovarian function among breast-feeding and post-partum non-breast-feeding women in a rural area of Mexico

The relationship between the return of menstruation and ovulation and the pattern of breastfeeding was studied in a group of 29 women in a rural area of Mexico; 8 non-breast feeding post-partum women were also studied. The return of ovulation was assessed by weekly determinations of urinary pregnanediol. The number of suckling episodes and supplementary feeds was recorded. The cumulative probability of resumption of menses for the breastfeeders was 28% and 52% at 3 and 6 months respectively and for the non-breastfeeders was 75% and 88%. The cumulative probability of ovulation for the breastfeeders was 28% 66% 69% and 72% at 3 6 9 and 12 months respectively and for the non-breastfeeders was 50% and 100% at 3 and 6 months. The earlier the introduction of supplements the earlier the return of ovulation. The non-ovulatory subjects maintained a higher frequency of suckling episodes than did the ovulatory subjects. The cumulative probability of pregnancy for the breast-feeders was 3% 7% 7% and 10% at 3 6 9 and 12 months respectively and for the non-breast-feeders was 13% 38% and 50% at 3 6 and 9 months. (authors modified)

The effects of three different regimens of oral contraceptives and three different intrauterine devices on the levels of hemoglobin, serum iron and iron binding capacity in anemic women

The effects on hemoglobin, iron and iron binding capacity (IBC) in 150 moderately anemic women of 1) a 21-day low-dose combined pill, 2) the same low-dose combined pill for 21 days, followed by 7 days of an iron-containing pill, 3) the same low-dose combined pill administered for 63 consecutive days, followed by 7 days of no pill intake, 4) Lippes IUD, 5) TCu 220C and 6) Progestasert were studied. The three pill regimens were associated with an increase in hemoglobin and serum iron after 12 months. However, the iron pill and 63-day schedule groups produced an increase in hemoglobin and iron at the 6th month ans a diminution of IBC at 12 months. The Lippes and TCu 220C groups did not show any change in hemoglobin, iron or iron binding capacity after 12 months. The Progestasert group showed an increase in hemoglobin and iron levels at 6 and 12 months, and a diminution of IBC at 12 months. The pill and Progestasert have advantages as contraceptives in anemic women.

Is the Copper T 380A device associated with an increased risk of removal due to bleeding and/or Pain? --An Analysis--

Previous studies have consistently shown that the family of the Copper T 380 devices is more effective in preventing accidental pregnancies than the inert, as well as most other, if not all, copper devices. However, a number of these studies also reported a higher removal rate due to bleeding and/or pain for the TCu 380A than for other devices. The programmatical importance of these findings prompted us to analyze the international multi-center randomized clinical trial datasets to examine this question on the new TCu 380A (ParaGard) recently marketed in the U.S. Our results, while confirming the inherent superior efficacy of the TCu 380A, did not reveal a significantly higher removal rate because of bleeding and/or pain among TCu 380A users than among users of the comparative devices, which included the Lippes Loop D, the TCu 200, the TCu 220 and the Multiload Cu 250 devices.

Effect of the lippes iud on the circulating levels of hemoglobin, hematocrit, serum iron and iron binding capacity in normal women

Abstract The levels of hemoglobin, hematocrit, serum iron and iron binding capacity were determined in 111 normal women before insertion and 3, 6, 12 and 15 months following the insertion of the Lippes IUD. There was not any statistically significant difference when the pre-insertion values were compared to those obtained 3 and 6 months after insertion. When the control levels were compared with those obtained 12 and 15 months after insertion, a statistically significant lowering of the hemoglobin and hematocrit values was observed. The levels of serum iron and iron binding capacity remained unchanged throughout the duration of the study. 19 cases became moderately anemic after the insertion of the Lippes IUD. The results also indicated that women with subnormal serum iron levels have a higher probability of developing anemia.

The use of biodegradable norethisterone implants as a 6-month contraceptive system

The effects of a 6-month contraceptive system of biodegradable norethisterone (NET) implants on the menstrual cycle, estradiol and progesterone levels, the presence of side effects, its contraceptive effectiveness, and the NET levels achieved were studied in a group of nine women. There was practically no disruption of the menstrual cycle and no important side effects. Ovulation was inhibited in four subjects, and another four subjects remained ovulatory. In all the subjects a cyclic secretion of estradiol was maintained. No pregnancies occurred. The circulatory levels of NET were very stable throughout the 6-month period of implant use.

Identification of Clinical and Programmatic Research Needs in Postpartum Contraception

A conference on Postpartum Contraception was held in Mexico City on September 17-19 1990 attended by 145 family planning policymakers service providers and researchers from 46 countries. The participants discussed contraceptive methods and service delivery and after the main meeting 19 representatives from 5 international agencies developed a process for selecting the highest priorities for clinical and program research. They had prepared 221 suggested research topics and at the meeting categorize these into 81 programmatic topics 64 clinical topics 43 both program and clinical topics. 3 working groups selected 10 most important topics in each category and then drafted a summary with objectives justification and future implications for each. Finally the participants rated all 30 topics on a scale of 1 to 5. The mean priorities of each topic ranged from 2.5 to 4.3 suggesting that the group members did not distinguish the topics in importance but considered them all rather important. The topic with the highest priority was a clinical study of the duration and contraceptive effectiveness of lactational amenorrhea in specific communities. Several other important topics involved timing of return to fertility best timing for IUD insertion integrating breastfeeding promotion into family planning programs introducing postpartum contraception into existing programs and assessing client preferences for postpartum family planning. The 30 project summaries are appended here.