Therapeutics · Ovulation Agents

Further clinical experience with clomiphene citrate

Macgregor AH, Johnson JE, Bunde CA

Published July 1968 Fertility and Sterility, 19(4), 616-622
DOI 10.1016/s0015-0282(16)36736-x PMID 5660246
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RRM Academy Synopsis

About 7 in 10 women ovulated on clomiphene in a 1968 case series

In 1968, a drug company pooled records on thousands of women who were not ovulating. About 7 out of 10 ovulated after taking clomiphene citrate, and about 3 out of 10 went on to get pregnant. No group was left untreated for comparison.

Key Findings

  • Among 2,196 pregnancies tracked, 1,744 delivered: 1,201 single live births (1,179 survived) and 136 multiple pregnancies producing 305 infants (251 survived).
  • Thirty-eight birth defects, including 5 with Down syndrome, occurred among the 1,744 completed pregnancies; no clear pattern was found among the defects.
  • Among 4,098 women who were not ovulating, about 70% ovulated after treatment, a rate that stayed steady since the earlier report; the pregnancy rate rose slightly to 31%.
  • Ovulation tracked with estrogen status: 79.6% of patients with good estrogen ovulated, versus 32.0% of those with absent estrogen (2,381 and 147 patients).
  • Among patients who were not ovulating, conception tracked the husband's fertility: 35.6% conceived when fertile, 24.1% when borderline, and 4.3% when infertile.

Interpretation

The report is a 1968 case series. A drug company gathered these records from many outside doctors. No group went untreated, so the results cannot show what would have happened without the drug. Doctors used their own categories to sort patients, and outcome reports were missing for 452 pregnancies. The birth-defect count was not measured against defect rates in the general population, so it cannot show whether the drug caused any defect. These are one company's clinical records from the 1960s, predating today's randomized-trial standards.

RRM Context

Clomiphene citrate is still used today to help women ovulate. This report shows an older approach. The authors sorted patients by diagnosis and concluded that an intact pituitary-ovarian axis is a prerequisite for the drug to work. Fewer women got pregnant than ovulated, and the authors reported multiple pregnancies up to tenfold more often in treatment cycles. Restorative reproductive medicine puts finding the cause first, ahead of simply restoring ovulation.

Abstract not indexed.

Topics

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Related research

Therapeutics › Ovulation Agents › Selective Estrogen Receptor Modulators · Pregnancy › Multiple Gestation › Multiple Birth Risks · Reproductive Endocrinology › Ovulation Physiology › Anovulation
PMID 5660246 5660246 DOI 10.1016/s0015-0282(16)36736-x 10.1016/s0015-0282(16)36736-x Macgregor et al. 1968, Macgregor 1968

Cite this article

Macgregor, A. H., Johnson, J. E., & Bunde, C. A. (1968). Further clinical experience with clomiphene citrate. Fertility and Sterility, 19(4), 616-622. https://doi.org/10.1016/s0015-0282(16)36736-x