A trial of daily vitamin supplementation as a means of reducing oral contraceptive side effects and discontinuation in Sri Lanka
Basnayake, S.; de Silva, S.V.; Miller, P.C.; Rogers, S.
Contraception 27(5): 465-472
1983
ISSN/ISBN: 0010-7824 PMID: 6349926 DOI: 10.1016/0010-7824(83)90043-4Document Number: 562749
A 4-cell, randomized, blind clinical trial was conducted in the city of Colombo and in 2 rural areas of Sri Lanka between September 1978-December 1980 to test whether a daily vitamin supplement would prevent oral contraceptive (OC) side effects and lead to improved continuation. 668 women received Norinyl with a daily vitamin supplement; 677 received Norinyl with placebo; 620 received Brevicon, a lower dose OC, with vitamin supplement; and 686 received Brevicon with placebo. The vitamin supplement contained 1.4 mg Bl, 1.7 mg B2, 10 mg B6, 4 mcg B12, .8 mg folate, 60 mg C, and 16 mg niacin. Over 90% of rural acceptors and 75% of urban acceptors were followed up. No differences in continuation rates at 3, 6, 9, or 12 months at any site approached statistical significance. Continuation was slightly higher for the vitamin group in Colombo and 1 rural site, but slightly higher for the placebo group in the other rural area. 9-month gross rates of termination by reason, site, and treatment on the whole showed greater differences by site than within treatments. Rates of unplanned pregnancy did not differ noticeably by treatment in any site, and no significant difference was found between treatments for rates of termination for either menstrual side effects, "other medical reasons or side effects," or other reasons. For most symptoms, placebo users showed higher levels of side effects than vitamin users, but the differences were neither substantial nor, in the 1st follow-up visit, significant.