Post-vaccination menstrual cycle and associated pre- and
post-menstrual symptoms
Of the total 5709 participants, 333(5.8%) developed irregularities of
the menstrual cycle with 32.7% (109/333) having frequent cycles (every
≤20 days), 63.7% (212/333) prolonged cycles (>38 days),
and 3.6% (12/333) intermenstrual bleed. A total of 301 out of 5709
participants (5.3%), noticed changes in the amount of bleeding during
menstruation, with 151(50.2%) having excessive bleeding, 147(48.8%)
scanty bleeding lasting for an average of 1-2 days with 0-1 pads/day,
and the remaining three participants (0.99%) had amenorrhea for 3-5
months followed by heavy bleeding. Of these 301 participants, 130
(43.2%) had both irregular cycles with changes in the amount and
duration of bleeding. The remaining 5408 (94.7%) participants observed
no change in the amount of bleeding during menstruation
post-vaccination. Furthermore, the irregularities of the menstrual cycle
were significantly higher (p=0.011) in the COVAXIN group (7.2%) as
compared to women who received the COVISHIELD vaccine (5.3%). Of the
total of 1245 women who received the COVAXIN vaccine, 3.2% complained
of frequent cycles (every <20 days) and 4.3% prolonged cycles
(>38 days), which was significantly higher than the women
who received the COVISHIELD vaccine (p=0.001). The mean±SD duration of
bleeding and the number of sanitary pads used per day during
menstruation in all the participants post-vaccination was 4.69±1.54
days, and 3.39±1.10 respectively. A total of 449(7.9%) participants
observed the new onset passage of clots during menstruation. No
statistically significant difference (p=0.346) was observed in the mean
duration of bleeding pre- and post-vaccination in both the vaccine
groups as depicted in Figure 2. A total of 721 (12.6%) participants
complained of newly developed or worsening pre- and post-menstrual
symptoms including severe dysmenorrhea with or without diarrhea
(55.3%), severe lower backache (9.4%), lower abdominal dragging pain
(18.0%), generalized weakness and body aches (8.9%), vaginal pain
(1.7%) and increased vaginal discharge (0.7%) along with some
non-specific symptoms in 5.96% participants including genital itching,
burning sensation in the vagina during menses, increased hair loss,
increased appetite, and insomnia during menstrual cycles. New onset or
worsening of pre- and post-menstrual symptoms were significantly higher
in the COVISHIELD group (p=0.031) with generalized weakness and body
pains as the main complaint (p=0.001). The comparison of menstrual cycle
patterns, and associated pre- and post-menstrual symptoms between women
who received COVISHIELD and COVAXIN vaccines is depicted in Table 2.