| LC control no. | sh 85090218 |
|---|---|
| Topical heading | Natural family planning--Ovulation method |
| Variant(s) | Billings ovulation method of birth control Cervical mucus method of birth control Natural family planning--Billings ovulation method Natural family planning--Cervical mucus method Ovulation method of birth control |
| See also | Cervix mucus Ovulation--Detection |
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