The Edinburgh-based company, which listed on the main market of the London Stock Exchange in April at 220p per share, saw its revenue for the first half of the year fall 2.7 per cent from £138.4 million to £134.7m.
Pre-tax losses widened from £10.3m to £38.1m, mainly as a result of costs associated with the initial public offering and the repayment of debt.
Chief executive Ian El-Mokadem insisted the business is trading profitably. He said there were around £45m of costs in the period related to the listing and the changes in financing.
Delays in production from Airbus and Boeing affected revenues in the period but Mr El-Mokadem pointed out the strong order books those companies have. In automotive, Exova was hit by a downturn in the testing of endurance of new vehicles.
Shares closed down 22p at 193p.
Exova, which employs around 210 people across Scotland, said revenue from aerospace dipped from £23.6m to £21.7m in the six months to June 30.
The oil and gas and industrial arm dropped from £42.3m to £39.9m. The product division, which includes transportation, fire and calibration testing, fell from £38.1m to £37.3m, while health sciences was up from £22.6m to £23.8m. The Middle East business also grew, from £11.8m to £12m.
Mr El-Mokadem said: "We have had headwinds in a couple of areas and very strong performance in other areas of the group. The medium-term outlook for the business remains positive.
"We are seeing increased levels of quotation activity in that area of the business, which is usually a good lead indicator for improving sales for the next year and beyond."
The company confirmed it is creating a larger laboratory in Aberdeen to serve its North Sea oil and gas customers, following a decision to stop doing some types of work in Norway.
Mr El-Mokadem said up to 10 jobs would be created before the end of this year, with scope for further growth.