Haru was born when Tsugumi was 17. She may as well have been 16 still when she got pregnant (possibly within half a year after middle-school graduation, depending on Tsugumi's birthday-date).
Suppose the infirmary scene where Tsugumi had a headache in that case are dizziness where she later knew she would be pregnant, the uniform in that scene is long sleeve so I guess they were in the first or second quarter (spring season) of the last school year, already with Tsugumi having 17 means that she turned years maybe in May or June giving birth to Haruko in February or March.
last edited at Aug 13, 2019 8:24PM