Gynaecology & Obstetrics Ferning of cervical mucus (fern test) is due to: A Presence of NaCl under progesterone effect B Presence of NaCl under estrogenic effect C LH/FSH D Mucus secretion by Glands 💡 Explanation Ferning of cervical mucus (fern test) is due to: ✓ Correct Answer: B. Presence of NaCl under estrogenic effect