Headache is common during pregnancy. Primary headache refers to conditions where the headache itself is the disorder, while secondary headaches are due to underlying diseases like stroke, venous thromboembolism, or pituitary tumours. A recent study has demonstrated Occipital nerve block to be an effective and quick-acting therapeutic modality for managing acute headaches in pregnancy, says Elisa T Bushman and Christina T Blanchard in a recent study published in Obstetrics & Gynecology.

This single-centre, unblinded, parallel, randomized controlled trial evaluated the efficacy of occipital nerve block compared with standard care, defined as acetaminophen with caffeine, for treating acute headaches in pregnancy. They measured headache improvement to a visual rating scale score of 3 or lower within 2 hours of initial therapy as the primary outcome. Secondary outcomes included serial visual rating scale scores, crossover or second-line therapy receipt, patient satisfaction, and perinatal outcomes.
Pregnant patients with headache and pain score higher than three on the visual rating scale were included and randomized to occipital nerve block or standard care (oral 650 mg acetaminophen and 200 mg caffeine). Crossover treatment was given at 2 hours and second-line treatment at 4 hours to those with worsening visual rating scale score or visual rating scale score higher than 3.
Key results of the study are:

Sixty-two participants were randomized, 31 to occipital nerve block and 31 to standard care.
There was no significant difference between groups considering the primary outcome, headache improvement, to a visual rating scale score of 3 or lower (64.5% vs 51.6%, P=.30).
The occipital nerve block group experienced lower median visual rating scale scores at 1 hour (2 vs 6 ), and more patients in the occipital nerve block group had visual rating scale scores of 3 or lower at 1 hour.
Among patients receiving crossover treatment at 2 hours, the standard care group had a lower visual rating scale score 1 hour after crossover to occipital nerve block than the occipital nerve block group receiving crossover to standard care.
There were no significant differences in second-line treatment, refractory headache, satisfaction, or complications.
Patients receiving occipital nerve block delivered earlier (36.6 weeks vs 37.8 weeks), but preterm birth did not differ between groups.
The study concluded that Occipital nerve block is an effective and quick-acting treatment option for acute headaches in pregnancy.
Reference:
Bushman ET, Blanchard CT, Cozzi GD, Davis AM, Harper L, Robbins LS, Jones B, Szychowski JM, Digre KB, Casey BM, Tita AT, Sinkey RG. Occipital Nerve Block Compared With Acetaminophen and Caffeine for Headache Treatment in Pregnancy: A Randomized Controlled Trial. Obstet Gynecol. 2023 Sep 28. doi: 10.1097/AOG.0000000000005386.