Pregnancy Outcomes with Paternal Exposure to Finasteride, a Synthetic 5-Alpha-Reductase Inhibitor: A Case Series

Abstract

Finasteride (a synthetic 5-alpha-reductase inhibitor) is used for the treatment of male pattern baldness and benign prostatic hyperplasia. There have been few reports on pregnancy outcomes after paternal exposure to finasteride either prior to or during pregnancy. Nineteen cases with documented paternal exposure to finasteride either prior to or during pregnancy were identified through the Korean Motherisk program. Detailed patient histories were obtained and each patient was followed from pregnancy through abortion or delivery. Of the 19 patients, 13 (68.4%) gave birth to normal full-term babies. The other six cases (31.6%) resulted in either spontaneous (n=3) or artificial (n=3) abortions. These results are consistent with previous animal studies demonstrating an increase in adverse outcomes with paternal exposure to finasteride.

Finasteride and Dutasteride for the Treatment of Male Androgenetic Alopecia: A Review of Efficacy and Reproductive Adverse Effects

“…52,53 Despite animal studies suggesting that finasteride teratogenicity after paternal exposure is unlikely due to the low concentration of finasteride absorbed in semen, there have been some reported cases of teratogenicity after paternal exposure and a possible association with spontaneous abortion. [54][55][56][57] For these reasons, it has been recommended by some researchers that males taking finasteride should avoid unprotected intercourse with a female partner who is or may be pregnant and discontinue finasteride before conceiving. 33,46,58 No mechanism has been elucidated for a finasteride-induced spontaneous abortion, although inadequate secretion of progesterone, uterine cervix stenosis, and sperm chromosomal abnormalities have been suggested as possible mechanisms.…”

“…33,46,58 No mechanism has been elucidated for a finasteride-induced spontaneous abortion, although inadequate secretion of progesterone, uterine cervix stenosis, and sperm chromosomal abnormalities have been suggested as possible mechanisms. 56,57…”

Paternal Finasteride Treatment Can Influence the Testicular Transcriptome Profile of Male Offspring—Preliminary Study

“…Initially, it was suggested that there was still no documented full-term pregnancy or live birth from couples in which the man had received finasteride [15], so caution has been advised regarding the use of finasteride by male members of couples who are planning to have children [22]. Probably for these reasons, in 2015 in South Korea, a clinical study was conducted which proved that in 19 couples with documented paternal exposure to finasteride, 13 couples (68.4%) gave birth to normal full-term babies, and six cases (31.6%) resulted in spontaneous (n = 3) or artificial (n = 3) abortions [23]. In our previous study [24], we observed a low number of pups in the litters of female rats fertilized by finasteride-treated male rats.…”